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Onodera K, Azekami K, Yahagi N, Kimura R, Kajimoto R, Yoshimura M, Kohyama S. Spontaneous disappearance of a small unruptured cerebral aneurysm in the clinoid segment of the internal carotid artery: A case report and literature review. Surg Neurol Int 2024; 15:299. [PMID: 39246771 PMCID: PMC11380906 DOI: 10.25259/sni_493_2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Accepted: 07/31/2024] [Indexed: 09/10/2024] Open
Abstract
Background Various degrees of thrombosis have been reported in patients with giant aneurysms. However, small, unruptured aneurysms rarely resolve spontaneously. Herein, we report a case of a small unruptured aneurysm in the clinoid segment (C3) of the left internal carotid artery (ICA) that showed almost complete occlusion at the 1-year follow-up. Case Description A 66-year-old woman developed a subarachnoid hemorrhage on the left side of the perimesencephalic cistern. Cerebral angiography performed on admission revealed no evidence of hemorrhage. Subsequent cerebral angiography on day 12 revealed a dissecting aneurysm on a branch of the superior cerebellar artery (SCA), and the patient underwent parental artery occlusion with 25% n-butyl-2-cyanoacrylate. The postoperative course was uneventful, and the patient was discharged on day 22 with a modified Rankin Scale score of 1. The 1 year follow-up cerebral angiogram demonstrated that the dissecting aneurysm in the SCA branch remained occluded. Notably, a small 2-mm unruptured aneurysm in the clinoid segment (C3) of the left ICA, which was present at the onset of subarachnoid hemorrhage, was almost completely occluded without intervention. Magnetic resonance angiography 1 year after spontaneous resolution of the aneurysm showed no apparent recurrence. Conclusion This case highlights that even small, unruptured aneurysms can develop spontaneous occlusions.
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Affiliation(s)
- Koki Onodera
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Kuya Azekami
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Noriyuki Yahagi
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Ryutaro Kimura
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Ryuta Kajimoto
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Masataka Yoshimura
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Shinya Kohyama
- Department of Endovascular Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan
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2
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Panneerselvam NK, Sudhir BJ, Kannath SK, Patnaik BSV. Influence of framing coil orientation and its shape on the hemodynamics of a basilar aneurysm model. Med Biol Eng Comput 2024:10.1007/s11517-024-03146-4. [PMID: 38856881 DOI: 10.1007/s11517-024-03146-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 05/28/2024] [Indexed: 06/11/2024]
Abstract
Aneurysms are bulges of an artery, which require clinical management solutions. Due to the inherent advantages, endovascular coil filling is emerging as the treatment of choice for intracranial aneurysms (IAs). However, after successful treatment of coil embolization, there is a serious risk of recurrence. It is well known that optimal packing density will enhance treatment outcomes. The main objective of endovascular coil embolization is to achieve flow stasis by enabling significant reduction in intra-aneurysmal flow and facilitate thrombus formation. The present study numerically investigates the effect of framing coil orientation on intra-aneurysmal hemodynamics. For the purpose of analysis, actual shape of the embolic coil is used, instead of simplified ideal coil shape. Typically used details of the framing coil are resolved for the analysis. However, region above the framing coil is assumed to be filled with a porous medium. Present simulations have shown that orientation of the framing coil loop (FCL) greatly influences the intra-aneurysmal hemodynamics. The FCLs which were placed parallel to the outlets of basilar tip aneurysm (Coil A) were found to reduce intra-aneurysmal flow velocity that facilitates thrombus formation. Involving the coil for the region is modeled using a porous medium model with a packing density of 20 % . The simulations indicate that the framing coil loop (FCL) has a significant influence on the overall outcome.
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Affiliation(s)
- Nisanth Kumar Panneerselvam
- Department of Applied Mechanics and Biomedical Engineering, Indian Institute of Technology Madras, Chennai, 600036, Tamilnadu, India
| | - B J Sudhir
- Department of Neurosurgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, 695011, Kerala, India.
| | - Santhosh K Kannath
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, 695011, Kerala, India
| | - B S V Patnaik
- Department of Applied Mechanics and Biomedical Engineering, Indian Institute of Technology Madras, Chennai, 600036, Tamilnadu, India.
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Fillingham P, Romero Bhathal J, Marsh LMM, Barbour MC, Kurt M, Ionita CN, Davies JM, Aliseda A, Levitt MR. Improving the accuracy of computational fluid dynamics simulations of coiled cerebral aneurysms using finite element modeling. J Biomech 2023; 157:111733. [PMID: 37527606 PMCID: PMC10528313 DOI: 10.1016/j.jbiomech.2023.111733] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 05/26/2023] [Accepted: 07/18/2023] [Indexed: 08/03/2023]
Abstract
Cerebral aneurysms are a serious clinical challenge, with ∼half resulting in death or disability. Treatment via endovascular coiling significantly reduces the chances of rupture, but the techniquehas failure rates of ∼20 %. This presents a pressing need to develop a method fordetermining optimal coildeploymentstrategies. Quantification of the hemodynamics of coiled aneurysms using computational fluid dynamics (CFD) has the potential to predict post-treatment outcomes, but representing the coil mass in CFD simulations remains a challenge. We use the Finite Element Method (FEM) for simulating patient-specific coil deployment for n = 4 ICA aneurysms for which 3D printed in vitro models were also generated, coiled, and scanned using ultra-high resolution synchrotron micro-CT. The physical and virtual coil geometries were voxelized onto a binary structured grid and porosity maps were generated for geometric comparison. The average binary accuracy score is 0.8623 and the average error in porosity map is 4.94 %. We then conduct patient-specific CFD simulations of the aneurysm hemodynamics using virtual coils geometries, micro-CT generated oil geometries, and using the porous medium method to represent the coil mass. Hemodynamic parameters including Neck Inflow Rate (Qneck) and Wall Shear Stress (WSS) were calculated for each of the CFD simulations. The average relative error in Qneck and WSS from CFD using FEM geometry were 6.6 % and 21.8 % respectively, while the error from CFD using a porous media approximation resulted in errors of 55.1 % and 36.3 % respectively; demonstrating a marked improvement in the accuracy of CFD simulations using FEM generated coil geometries.
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Affiliation(s)
- Patrick Fillingham
- Department of Neurological Surgery, University of Washington, Seattle, WA, United States.
| | | | - Laurel M M Marsh
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Michael C Barbour
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Mehmet Kurt
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Ciprian N Ionita
- Department of Biomedical Engineering, University at Buffalo, Buffalo, NY, United States
| | - Jason M Davies
- Department of Neurosurgery, University at Buffalo, Buffalo, NY, United States
| | - Alberto Aliseda
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Michael R Levitt
- Department of Neurological Surgery, University of Washington, Seattle, WA, United States; Department of Mechanical Engineering, University of Washington, Seattle, WA, United States; Department of Radiology, University of Washington, Seattle, WA, United States
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4
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Bass DI, Marsh LMM, Fillingham P, Lim D, Chivukula VK, Kim LJ, Aliseda A, Levitt MR. Modeling the Mechanical Microenvironment of Coiled Cerebral Aneurysms. J Biomech Eng 2023; 145:041005. [PMID: 36193892 PMCID: PMC9791668 DOI: 10.1115/1.4055857] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 09/09/2022] [Indexed: 12/30/2022]
Abstract
Successful occlusion of cerebral aneurysms using coil embolization is contingent upon stable thrombus formation, and the quality of the thrombus depends upon the biomechanical environment. The goal of this study was to investigate how coil embolization alters the mechanical micro-environment within the aneurysm dome. Inertialess particles were injected in three-dimensional, computational simulations of flow inside patient aneurysms using patient-specific boundary conditions. Coil embolization was simulated as a homogenous porous medium of known permeability and inertial constant. Lagrangian particle tracking was used to calculate the residence time and shear stress history for particles in the flow before and after treatment. The percentage of particles entering the aneurysm dome correlated with the neck surface area before and after treatment (pretreatment: R2 = 0.831, P < 0.001; post-treatment: R2 = 0.638, P < 0.001). There was an inverse relationship between the change in particles entering the dome and coil packing density (R2 = 0.600, P < 0.001). Following treatment, the particles with the longest residence times tended to remain within the dome even longer while accumulating lower shear stress. A significant correlation was observed between the treatment effect on residence time and the ratio of the neck surface area to porosity (R2 = 0.390, P = 0.007). The results of this study suggest that coil embolization triggers clot formation within the aneurysm dome via a low shear stress-mediated pathway. This hypothesis links independently observed findings from several benchtop and clinical studies, furthering our understanding of this treatment strategy.
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Affiliation(s)
- David I. Bass
- Department of Neurological Surgery, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104
| | - Laurel M. M. Marsh
- Department of Mechanical Engineering, University of Washington, 3900 East Stevens Way NE, Box 352600, Seattle, WA 98195
| | - Patrick Fillingham
- Department of Neurological Surgery, Stroke & Applied Neuroscience Center, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104
| | - Do Lim
- Department of Neurological Surgery, Stroke & Applied Neuroscience Center, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104
| | - V. Keshav Chivukula
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, 150 West University Building, Melbourne, FL 32901
| | - Louis J. Kim
- Department of Neurological Surgery, Stroke & Applied Neuroscience Center, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104; Department of Radiology, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104
| | - Alberto Aliseda
- Department of Mechanical Engineering, Stroke & Applied Neuroscience Center, University of Washington, 3900 East Stevens Way NE, Box 352600, Seattle, WA 98195; Department of Neurological Surgery, Stroke & Applied Neuroscience Center, University of Washington, 3900 East Stevens Way NE, Box 352600, Seattle, WA 98195
| | - Michael R. Levitt
- Department of Neurological Surgery, Stroke & Applied Neuroscience Center, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104; Department of Radiology, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104; Department of Mechanical Engineering, University of Washington, 325 9th Avenue, Box 359924, Seattle, WA 98104
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5
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Kamada H, Nakamura M, Ota H, Higuchi S, Takase K. Blood flow analysis with computational fluid dynamics and 4D-flow MRI for vascular diseases. J Cardiol 2022; 80:386-396. [PMID: 35718672 DOI: 10.1016/j.jjcc.2022.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 10/31/2022]
Abstract
Both computational fluid dynamics (CFD) and time-resolved, three-dimensional, phase-contrast, magnetic resonance imaging (4D-flow MRI) enable visualization of time-varying blood flow structures and quantification of blood flow in vascular diseases. However, they are totally different. CFD is a method to calculate blood flow by solving the governing equations of fluid mechanics, so the obtained flow field is somewhat virtual. On the other hand, 4D-flow MRI measures blood flow in vivo, thus the flow is real. Recently, with the development and enhancement of computers, medical imaging techniques, and related software, blood flow analysis has become more accessible to clinicians and its usefulness in vascular diseases has been demonstrated. In this review, we have outlined the methods and characteristics of CFD and 4D-flow MRI, respectively. We have discussed the differences in the characteristics between both methods; reviewed the milestones achieved by blood flow analysis in various vascular diseases; and discussed the usefulness, challenges, and limitations of blood flow analysis. We have discussed the difficulties and limitations of current blood flow analysis. We have also discussed our views on future directions.
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Affiliation(s)
- Hiroki Kamada
- Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Japan.
| | - Masanori Nakamura
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan
| | - Hideki Ota
- Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Japan
| | - Satoshi Higuchi
- Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Japan
| | - Kei Takase
- Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Japan
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6
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Chung J, Ko JH. An Efficient Method for Aneurysm Volume Quantification Applicable in Any Shape and Modalities. J Korean Neurosurg Soc 2021; 64:514-523. [PMID: 34185985 PMCID: PMC8273770 DOI: 10.3340/jkns.2020.0255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/14/2020] [Indexed: 02/08/2023] Open
Abstract
Objective Aneurysm volume quantification (AVQ) using the equation of ellipsoid volume is widely used although it is inaccurate. Furthermore, AVQ with 3-dimensional (3D) rendered data has limitations in general use. A novel universal method for AVQ is introduced for any diagnostic modality and application to any shape of aneurysms.
Methods Relevant AVQ studies published from January 1997 to June 2019 were identified to determine common methods of AVQ. The basic idea is to eliminate the normal artery volume from 3D model with the aneurysm. After Digital Imaging and Communications in Medicine (DICOM) data is converted and exported to stereolithography (STL) file format, the 3D STL model is modified to remove the aneurysm and the volume difference between the 3D model with/without the aneurysm is defined as the aneurysm volume. Fifty randomly selected aneurysms from DICOM database were used to validate the different AVQ methods.
Results We reviewed and categorized AVQ methods in 121 studies. Approximately 60% used the ellipsoid method, while 24% used the 3D model. For 50 randomly selected aneurysms, volumes were measured using 3D Slicer, RadiAnt, and ellipsoid method. Using 3D Slicer as the reference, the ratios of mean difference to mean volume obtained by RadiAnt and ellipsoid method were -1.21±7.46% and 4.04±30.54%, respectively. The deviations between RadiAnt and 3D Slicer were small despite of aneurysm shapes, but those of ellipsoid method and 3D Slicer were large.
Conclusion In spite of inaccuracy, ellipsoid method is still mostly used. We propose a novel universal method for AVQ that is valid, low cost, and easy to use.
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Affiliation(s)
- Jaewoo Chung
- Department of Neurosurgery, Dankook University College of Medicine, Cheonan, Korea
| | - Jung Ho Ko
- Department of Neurosurgery, Dankook University College of Medicine, Cheonan, Korea
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Lee KS, Zhang JJY, Nguyen V, Han J, Johnson JN, Kirollos R, Teo M. The evolution of intracranial aneurysm treatment techniques and future directions. Neurosurg Rev 2021; 45:1-25. [PMID: 33891216 PMCID: PMC8827391 DOI: 10.1007/s10143-021-01543-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/21/2021] [Accepted: 04/07/2021] [Indexed: 01/06/2023]
Abstract
Treatment techniques and management guidelines for intracranial aneurysms (IAs) have been continually developing and this rapid development has altered treatment decision-making for clinicians. IAs are treated in one of two ways: surgical treatments such as microsurgical clipping with or without bypass techniques, and endovascular methods such as coiling, balloon- or stent-assisted coiling, or intravascular flow diversion and intrasaccular flow disruption. In certain cases, a single approach may be inadequate in completely resolving the IA and successful treatment requires a combination of microsurgical and endovascular techniques, such as in complex aneurysms. The treatment option should be considered based on factors such as age; past medical history; comorbidities; patient preference; aneurysm characteristics such as location, morphology, and size; and finally the operator’s experience. The purpose of this review is to provide practicing neurosurgeons with a summary of the techniques available, and to aid decision-making by highlighting ideal or less ideal cases for a given technique. Next, we illustrate the evolution of techniques to overcome the shortfalls of preceding techniques. At the outset, we emphasize that this decision-making process is dynamic and will be directed by current best scientific evidence, and future technological advances.
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Affiliation(s)
- Keng Siang Lee
- Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, UK. .,Department of Neurosurgery, Bristol Institute of Clinical Neuroscience, Southmead Hospital, Bristol, UK.
| | - John J Y Zhang
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Vincent Nguyen
- Department of Neurosurgery, Bristol Institute of Clinical Neuroscience, Southmead Hospital, Bristol, UK.,Department of Neurosurgery, University of Tennessee Health Sciences Center, Memphis, TN, USA
| | - Julian Han
- Department of Neurosurgery, National Neuroscience Institute, Singapore, Singapore
| | - Jeremiah N Johnson
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA
| | - Ramez Kirollos
- Department of Neurosurgery, National Neuroscience Institute, Singapore, Singapore.,Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Addenbrooke's Hospital, Cambridge, UK
| | - Mario Teo
- Department of Neurosurgery, Bristol Institute of Clinical Neuroscience, Southmead Hospital, Bristol, UK
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8
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Wiśniewski K, Tomasik B, Tyfa Z, Reorowicz P, Bobeff EJ, Stefańczyk L, Posmyk BJ, Jóźwik K, Jaskólski DJ. Porous Media Computational Fluid Dynamics and the Role of the First Coil in the Embolization of Ruptured Intracranial Aneurysms. J Clin Med 2021; 10:jcm10071348. [PMID: 33805169 PMCID: PMC8037793 DOI: 10.3390/jcm10071348] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/28/2021] [Accepted: 03/20/2021] [Indexed: 11/22/2022] Open
Abstract
Background: The objective of our project was to identify a late recanalization predictor in ruptured intracranial aneurysms treated with coil embolization. This goal was achieved by means of a statistical analysis followed by a computational fluid dynamics (CFD) with porous media modelling approach. Porous media CFD simulated the hemodynamics within the aneurysmal dome after coiling. Methods: Firstly, a retrospective single center analysis of 66 aneurysmal subarachnoid hemorrhage patients was conducted. The authors assessed morphometric parameters, packing density, first coil volume packing density (1st VPD) and recanalization rate on digital subtraction angiograms (DSA). The effectiveness of initial endovascular treatment was visually determined using the modified Raymond–Roy classification directly after the embolization and in a 6- and 12-month follow-up DSA. In the next step, a comparison between porous media CFD analyses and our statistical results was performed. A geometry used during numerical simulations based on a patient-specific anatomy, where the aneurysm dome was modelled as a separate, porous domain. To evaluate hemodynamic changes, CFD was utilized for a control case (without any porosity) and for a wide range of porosities that resembled 1–30% of VPD. Numerical analyses were performed in Ansys CFX solver. Results: A multivariate analysis showed that 1st VPD affected the late recanalization rate (p < 0.001). Its value was significantly greater in all patients without recanalization (p < 0.001). Receiver operating characteristic curves governed by the univariate analysis showed that the model for late recanalization prediction based on 1st VPD (AUC 0.94 (95%CI: 0.86–1.00) is the most important predictor of late recanalization (p < 0.001). A cut-off point of 10.56% (sensitivity—0.722; specificity—0.979) was confirmed as optimal in a computational fluid dynamics analysis. The CFD results indicate that pressure at the aneurysm wall and residual flow volume (blood volume with mean fluid velocity > 0.01 m/s) within the aneurysmal dome tended to asymptotically decrease when VPD exceeded 10%. Conclusions: High 1st VPD decreases the late recanalization rate in ruptured intracranial aneurysms treated with coil embolization (according to our statistical results > 10.56%). We present an easy intraoperatively calculable predictor which has the potential to be used in clinical practice as a tip to improve clinical outcomes.
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Affiliation(s)
- Karol Wiśniewski
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcińskiego 22, 90-153 Lodz, Poland; (E.J.B.); (B.J.P.); (D.J.J.)
- Correspondence: ; Tel.: +48-(042)-677-6770
| | - Bartłomiej Tomasik
- Department of Biostatistics and Translational Medicine, Medical University of Lodz, 15 Mazowiecka St., 92-215 Lodz, Poland; or
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Zbigniew Tyfa
- Institute of Turbomachinery, Lodz University of Technology, Medical Apparatus Division, Wolczanska 219/223, 90-924 Lodz, Poland; (Z.T.); (P.R.); (K.J.)
| | - Piotr Reorowicz
- Institute of Turbomachinery, Lodz University of Technology, Medical Apparatus Division, Wolczanska 219/223, 90-924 Lodz, Poland; (Z.T.); (P.R.); (K.J.)
| | - Ernest J. Bobeff
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcińskiego 22, 90-153 Lodz, Poland; (E.J.B.); (B.J.P.); (D.J.J.)
| | - Ludomir Stefańczyk
- Department of Radiology—Diagnostic Imaging, Medical University of Lodz, Kopcińskiego 22, 90-153 Lodz, Poland;
| | - Bartłomiej J. Posmyk
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcińskiego 22, 90-153 Lodz, Poland; (E.J.B.); (B.J.P.); (D.J.J.)
| | - Krzysztof Jóźwik
- Institute of Turbomachinery, Lodz University of Technology, Medical Apparatus Division, Wolczanska 219/223, 90-924 Lodz, Poland; (Z.T.); (P.R.); (K.J.)
| | - Dariusz J. Jaskólski
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcińskiego 22, 90-153 Lodz, Poland; (E.J.B.); (B.J.P.); (D.J.J.)
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Saqr KM, Rashad S, Tupin S, Niizuma K, Hassan T, Tominaga T, Ohta M. What does computational fluid dynamics tell us about intracranial aneurysms? A meta-analysis and critical review. J Cereb Blood Flow Metab 2020; 40:1021-1039. [PMID: 31213162 PMCID: PMC7181089 DOI: 10.1177/0271678x19854640] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Despite the plethora of published studies on intracranial aneurysms (IAs) hemodynamic using computational fluid dynamics (CFD), limited progress has been made towards understanding the complex physics and biology underlying IA pathophysiology. Guided by 1733 published papers, we review and discuss the contemporary IA hemodynamics paradigm established through two decades of IA CFD simulations. We have traced the historical origins of simplified CFD models which impede the progress of comprehending IA pathology. We also delve into the debate concerning the Newtonian fluid assumption used to represent blood flow computationally. We evidently demonstrate that the Newtonian assumption, used in almost 90% of studies, might be insufficient to describe IA hemodynamics. In addition, some fundamental properties of the Navier-Stokes equation are revisited in supplementary material to highlight some widely spread misconceptions regarding wall shear stress (WSS) and its derivatives. Conclusively, our study draws a roadmap for next-generation IA CFD models to help researchers investigate the pathophysiology of IAs.
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Affiliation(s)
- Khalid M Saqr
- Biomedical Flow Dynamics Laboratory, Institute of Fluid Science, Tohoku University, Sendai, Miyagi, Japan.,Department of Mechanical Engineering, College of Engineering and Technology, Arab Academy for Science, Technology and Maritime Transport, Alexandria, Egypt
| | - Sherif Rashad
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Simon Tupin
- Biomedical Flow Dynamics Laboratory, Institute of Fluid Science, Tohoku University, Sendai, Miyagi, Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.,Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
| | - Tamer Hassan
- Department of Neurosurgery, Alexandria University School of Medicine, Azarita Medical Campus, Alexandria, Egypt
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Makoto Ohta
- Biomedical Flow Dynamics Laboratory, Institute of Fluid Science, Tohoku University, Sendai, Miyagi, Japan
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Fujimura S, Takao H, Suzuki T, Uchiyama Y, Tanaka K, Otani K, Ishibashi T, Fukudome K, Mamori H, Yamamoto M, Murayama Y. Blood Flow Analysis in Coil Embolized Aneurysms: Difference between Porous Media and Real Coil Geometry Model. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:1331-1334. [PMID: 30440637 DOI: 10.1109/embc.2018.8512482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To clarify the mechanism of aneurysmal recanalization, it is necessary to understand the characteristics of the blood flow inside the aneurysm in particular the flow resistance generated by the coil. In studies using computational fluid dynamics (CFD), mainly two approaches have been used to model the coil embolized aneurysm; modeling the coils as porous media or by real coil geometries. In this study, we calculated the pressure drop along a vessel through a coiled region modeled as porous media or by real coil geometry and compared the pressure drop generated by the two coil models. The porous media model was described by Darcy's law and Ergun's equation, while the real coil geometry was generated using finite element method (FEM) structural analysis. We calculated the pressure drop for inlet velocities from 0.1 m/s to 1.0 m/s in steps of 0.1 m/s. Our results indicated that the porous media model may produce larger pressure drops than the real coil geometry model under low packing density. The value of the pressure drop was also changed due to the difference of coil distribution even if the packing density was the same.
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11
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Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms. PLoS One 2017; 12:e0190222. [PMID: 29284057 PMCID: PMC5746265 DOI: 10.1371/journal.pone.0190222] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 12/11/2017] [Indexed: 11/19/2022] Open
Abstract
Objective This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD). Method A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s. Result Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01–1.11; P = 0.016). Conclusion The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms.
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12
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Fujimura S, Takao H, Suzuki T, Dahmani C, Ishibashi T, Mamori H, Yamamoto M, Murayama Y. Hemodynamics and coil distribution with changing coil stiffness and length in intracranial aneurysms. J Neurointerv Surg 2017; 10:797-801. [PMID: 29259122 PMCID: PMC6204941 DOI: 10.1136/neurintsurg-2017-013457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/25/2017] [Accepted: 11/27/2017] [Indexed: 12/02/2022]
Abstract
Purpose The purpose of this study was to investigate hemodynamics and coil distribution with changing coil stiffness and length using the finite element method (FEM) and computational fluid dynamics (CFD) analysis. Methods Basic side-wall and bifurcation type aneurysm models were used. Six types of coil models were generated by changing the coil stiffness and length, based on commercially available embolic coils. Coil embolization was simulated using FEM. CFD was performed to characterize the hemodynamics in the aneurysms after embolization. Coil distribution and velocity reduction in the aneurysms were evaluated. Results The median value of radial coil distribution was shifted from the center to the outer side of the aneurysmal dome by changing coil stiffness: harder coils entered the outer side of the aneurysmal dome more easily. Short coils were more distributed at the neck region, since their small size made it easy for them to enter the tighter area. CFD results also indicated that velocity in the aneurysm was effectively reduced when the coils were more distributed at the neck region and the outer side of the aneurysmal dome because of the disturbance in blood inflow. Conclusions It is easier for coils to enter the outer side of the aneurysmal sphere when they are harder. If coils are short, they can enter tighter areas more easily. In addition, high coil density at the outer side of the aneurysmal dome and at the neck region is important to achieve effective velocity reduction.
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Affiliation(s)
- Soichiro Fujimura
- Graduate School of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan.,Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyuki Takao
- Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan.,Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Suzuki
- Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan.,Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Chihebeddine Dahmani
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan.,Siemens Healthcare KK, Tokyo, Japan
| | - Toshihiro Ishibashi
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroya Mamori
- Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Makoto Yamamoto
- Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Yuichi Murayama
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
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13
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Sugiyama SI, Niizuma K, Sato K, Rashad S, Kohama M, Endo H, Endo T, Matsumoto Y, Ohta M, Tominaga T. Blood Flow Into Basilar Tip Aneurysms. Stroke 2016; 47:2541-7. [DOI: 10.1161/strokeaha.116.013555] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 08/15/2016] [Indexed: 12/28/2022]
Abstract
Background and Purpose—
Hemodynamic forces may play a role in the recanalization of coiled aneurysms. The purpose of this study was to investigate the influence of presurgical hemodynamics on the efficacy of coil embolization for basilar tip aneurysms.
Methods—
We identified 82 patients who underwent endovascular coil embolization for basilar tip aneurysms with a follow-up of >1 year. Presurgical hemodynamics were investigated using computational fluid dynamics with 3-dimensional data derived from rotational angiography. During postprocessing, we quantified the rate of net flow entering the aneurysm through its neck and calculated the proportion of the aneurysmal inflow rate to the basilar artery flow rate. In addition, we investigated the correlation between the basilar bifurcation configuration and the hemodynamics.
Results—
Twenty-five of the 82 patients were excluded because of difficult vascular geometry reconstruction. Among the 57 examined patients, angiographic recanalization was observed in 19 patients (33.3%). The proportion of the aneurysmal inflow rate to the basilar artery flow rate and a coil packing density <30% were independent and significant predictors for the recanalization of coiled aneurysms. Additional investigation revealed that a small branch angle formed by the basilar artery and the posterior cerebral artery increased blood flow into the aneurysm.
Conclusions—
The proportion of the aneurysmal inflow rate to the basilar artery flow rate, influenced by the basilar bifurcation configuration, was an independent and significant predictor for recanalization after coil embolization in basilar tip aneurysms.
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Affiliation(s)
- Shin-ichiro Sugiyama
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Kuniyasu Niizuma
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Kenichi Sato
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Sherif Rashad
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Misaki Kohama
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Hidenori Endo
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Toshiki Endo
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Yasushi Matsumoto
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Makoto Ohta
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
| | - Teiji Tominaga
- From the Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan (S.-i.S., K.N., S.R., T.T.); Graduate School of Biomedical Engineering (S.-i.S., M.O.) and Institute of Fluid Science (M.O.), Tohoku University, Sendai, Japan; and Department of Neuroanesthesia (S.-i.S., M.K.), Department of Neuroendovascular Therapy (K.S., Y.M.), and Department of Neurosurgery (H.E., T.E.), Kohnan Hospital, Sendai, Japan
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Otani T, Ii S, Shigematsu T, Fujinaka T, Hirata M, Ozaki T, Wada S. Computational study for the effects of coil configuration on blood flow characteristics in coil-embolized cerebral aneurysm. Med Biol Eng Comput 2016; 55:697-710. [DOI: 10.1007/s11517-016-1541-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 06/29/2016] [Indexed: 11/28/2022]
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15
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Kaesmacher J, Müller-Leisse C, Huber T, Boeckh-Behrens T, Haller B, Shiban E, Friedrich B, Zimmer C, Dorn F, Prothmann S. Volume versus standard coils in the treatment of intracranial aneurysms. J Neurointerv Surg 2015; 8:1034-40. [PMID: 26491040 DOI: 10.1136/neurintsurg-2015-012014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/28/2015] [Indexed: 11/03/2022]
Abstract
BACKGROUND Volume coils were developed to improve occlusion rates of intracranial aneurysms. Previous studies have shown increased packing density and comparable occlusion rates, but subgroup analyses of aneurysm size have not been carried out. OBJECTIVE To evaluate the safety and efficacy of the Penumbra Coil 400 (PC400) system in treating intracranial aneurysms compared with standard diameter coils. METHODS A monocentric retrospective case review of 260 aneurysms in 233 patients was carried out. In 37 aneurysms the PC400 system was used, while 223 aneurysms were treated with conventional coils. Previously treated aneurysms and aneurysms treated with flow diverters were excluded. Aneurysm and procedure characteristics, packing density, postprocedural and follow-up occlusion grades as well as coil compaction were evaluated. RESULTS Aneurysms treated with PC400 coils had higher volume (218.9 vs 47.1 mm(3), p<0.001), wider necks (3.0 vs 2.5 mm, p=0.005), and greater dome/neck ratio (2.0 vs 1.6, p=0.001) in comparison with aneurysms treated with conventional coils. Compared with controls, in the PC400 group we achieved higher packing densities (43.2% vs 34.4%, p<0.001; in aneurysms ≥7 mm 42.2% vs 27.8%, p<0.001). On follow-up angiography we observed less coil compaction (23.8% vs 64.3%, p=0.003) and less aneurysm recurrence (14.3% vs 40.5%, p=0.046) in aneurysms ≥7 mm when using the PC400 system. CONCLUSIONS Use of the PC400 system as opposed to conventional coils suggests that the PC400 system is safe and effective in treating intracranial aneurysms. Despite having been applied in a potentially more difficult-to-treat group, the use of PC400 was associated with less coil compaction and aneurysm recurrence in aneurysms ≥7 mm.
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Affiliation(s)
- Johannes Kaesmacher
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Christina Müller-Leisse
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Thomas Huber
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Tobias Boeckh-Behrens
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Bernhard Haller
- Institut für Statistik und Epidemiologie (IMSE), Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Ehab Shiban
- Klinik für Neurochirurgie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Benjamin Friedrich
- Klinik und Poliklinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Leipzig, Leipzig, Germany
| | - Claus Zimmer
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Franziska Dorn
- Abteilung für Neuroradiologie, Klinikum Großhadern, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Sascha Prothmann
- Abteilung für diagnostische und interventionelle Neuroradiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
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16
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Hybrid stent device of flow-diverting effect and stent-assisted coil embolization formed by fractal structure. Med Biol Eng Comput 2015; 54:831-41. [DOI: 10.1007/s11517-015-1374-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 08/11/2015] [Indexed: 10/23/2022]
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17
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Halabian M, Karimi A, Beigzadeh B, Navidbakhsh M. A NUMERICAL STUDY ON THE HEMODYNAMIC AND SHEAR STRESS OF DOUBLE ANEURYSM THROUGH S-SHAPED VESSEL. BIOMEDICAL ENGINEERING-APPLICATIONS BASIS COMMUNICATIONS 2015. [DOI: 10.4015/s1016237215500337] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abdominal aortic aneurysm (AAA) is a degenerative disease defined as the abnormal ballooning of the abdominal aorta (AA) wall which is usually caused by atherosclerosis. The aneurysm grows larger and eventually ruptures if it is not diagnosed and treated. Aneurysms occur mostly in the aorta, the main artery of the chest and abdomen. The aorta carries blood flow from the heart to all parts of the body, including the vital organs, the legs, and feet. The objective of the present study is to investigate the combined effects of aneurysm and curvature on flow characteristics in S-shaped bends with sweep angle of 90° at Reynolds number of 900. The fluid mechanics of blood flow in a curved artery with abnormal aortic is studied through a mathematical analysis and employing Cosmos flow simulation. Blood is modeled as an incompressible non-Newtonian fluid and the flow is assumed to be steady and laminar. Hemodynamic characteristics are analyzed. Grid independence is tested on three successively refined meshes. It is observed that the abrupt expansion induced by AAA results in an immensely disturbed regime. The results may have implications not only for understanding the mechanical behavior of the blood flow inside an aneurysm artery but also for investigating the mechanical behavior of the blood flow in different arterial diseases, such as atherosclerosis.
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Affiliation(s)
- Mahdi Halabian
- Tissue Engineering and Biological Systems Research Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846, Iran
| | - Alireza Karimi
- Tissue Engineering and Biological Systems Research Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846, Iran
| | - Borhan Beigzadeh
- Tissue Engineering and Biological Systems Research Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846, Iran
| | - Mahdi Navidbakhsh
- Tissue Engineering and Biological Systems Research Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846, Iran
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18
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Sadato A, Adachi K, Hayakawa M, Kato Y, Hirose Y. Effects of anatomic characteristics of aneurysms on packing density in endovascular coil embolization: analysis of a single center's experience. Neurosurg Rev 2015. [PMID: 26223542 DOI: 10.1007/s10143-015-0658-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
When embolizing cerebral aneurysms, dense coil packing may prevent recanalization but this may be influenced by the aneurysm morphology. We have analyzed retrospectively the relationship between anatomic features and the volumetric coil packing density. We analyzed 452 aneurysms in 434 patients treated by coil embolization without stenting, expressing packing density as volume embolization ratio (VER, volume of inserted coils/aneurysm volume). Six morphological variables (neck width, height, maximum diameter, dome to neck ratio (DNR), and aspect ratio), aneurysm location, and whether the aneurysm was ruptured or unruptured were analyzed with respect to dense (VER ≥20%) or loose (VER <20%) packing densities, using logistic regression analysis and ROC analysis. Among 452 aneurysms, VERs >20% were achieved for 272 aneurysms, with a mean VER of 24.7%. The mean VER of the remaining 180 aneurysms was 15.6%. In univariate analyses, the predictors for dense packing were having an anterior circulation, DNR, aspect ratio, and neck width. In multivariate analysis, the independent predictors were smaller neck width (odds ratio (OR) 0.8735; 95% confidence interval (CI) 0.7635-0.9993) and larger aspect ratio (OR 1.6679; 95% CI 1.0460-2.6594). ROC analysis showed optimal cutoff values for an aspect ratio of 1.35 (sensitivity 69.5%, specificity 51.7%) and a neck width of 3.13 mm (sensitivity 51.1%, specificity 27.8%). Although dense coil packing is still difficult to achieve in wide-necked aneurysms without the use of stents, packing with VER >20% is expected to be achieved when the height is 1.35 times larger than the neck width.
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Affiliation(s)
- Akiyo Sadato
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan.
| | - Kazuhide Adachi
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Motoharu Hayakawa
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Yoko Kato
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Yuichi Hirose
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
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19
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Predictors of treatment failure following coil embolization of intracranial aneurysms. J Clin Neurosci 2015; 22:1275-81. [DOI: 10.1016/j.jocn.2015.03.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 03/02/2015] [Indexed: 11/23/2022]
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20
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Chueh JY, Vedantham S, Wakhloo AK, Carniato SL, Puri AS, Bzura C, Coffin S, Bogdanov AA, Gounis MJ. Aneurysm permeability following coil embolization: packing density and coil distribution. J Neurointerv Surg 2014; 7:676-81. [PMID: 25031179 PMCID: PMC4552888 DOI: 10.1136/neurintsurg-2014-011289] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 06/29/2014] [Indexed: 11/25/2022]
Abstract
Background Rates of durable aneurysm occlusion following coil embolization vary widely, and a better understanding of coil mass mechanics is desired. The goal of this study is to evaluate the impact of packing density and coil uniformity on aneurysm permeability. Methods Aneurysm models were coiled using either Guglielmi detachable coils or Target coils. The permeability was assessed by taking the ratio of microspheres passing through the coil mass to those in the working fluid. Aneurysms containing coil masses were sectioned for image analysis to determine surface area fraction and coil uniformity. Results All aneurysms were coiled to a packing density of at least 27%. Packing density, surface area fraction of the dome and neck, and uniformity of the dome were significantly correlated (p<0.05). Hence, multivariate principal components-based partial least squares regression models were used to predict permeability. Similar loading vectors were obtained for packing and uniformity measures. Coil mass permeability was modeled better with the inclusion of packing and uniformity measures of the dome (r2=0.73) than with packing density alone (r2=0.45). The analysis indicates the importance of including a uniformity measure for coil distribution in the dome along with packing measures. Conclusions A densely packed aneurysm with a high degree of coil mass uniformity will reduce permeability.
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Affiliation(s)
- Ju-Yu Chueh
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Srinivasan Vedantham
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ajay K Wakhloo
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Sarena L Carniato
- PreClinical Science, Stryker Neurovascular, Fremont, California, USA
| | - Ajit S Puri
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Conrad Bzura
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Spencer Coffin
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Alexei A Bogdanov
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Matthew J Gounis
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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21
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Goubergrits L, Schaller J, Kertzscher U, Woelken T, Ringelstein M, Spuler A. Hemodynamic impact of cerebral aneurysm endovascular treatment devices: coils and flow diverters. Expert Rev Med Devices 2014; 11:361-73. [PMID: 24918904 DOI: 10.1586/17434440.2014.925395] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Coils and flow diverters or stents are devices successfully used to treat cerebral aneurysms. Treatment aims to reduce intra-aneurysmal flow, thereby separating the aneurysmal sac from the blood circulation. The focus and this manuscript combining literature review and our original research is an analysis of changes in aneurysmal hemodynamics caused by endovascular treatment devices. Knowledge of post-treatment hemodynamics is a path to successful long-term treatment. Summarizing findings on hemodynamic impact of treatment devices, we conclude: coiling and stenting do not affect post-treatment intra-aneurysmal pressure, but significantly alter aneurysmal hemodynamics through flow reduction and a change in flow structure. The impact of treatment devices on aneurysmal flow depends, however, on a set of parameters including device geometry, course of placement, parent vessel and aneurysm geometry.
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Affiliation(s)
- Leonid Goubergrits
- Biofluid Mechanics Laboratory, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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Mascitelli JR, Moyle H, Oermann EK, Polykarpou MF, Patel AA, Doshi AH, Gologorsky Y, Bederson JB, Patel AB. An update to the Raymond-Roy Occlusion Classification of intracranial aneurysms treated with coil embolization. J Neurointerv Surg 2014; 7:496-502. [PMID: 24898735 DOI: 10.1136/neurintsurg-2014-011258] [Citation(s) in RCA: 232] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 05/02/2014] [Indexed: 11/04/2022]
Abstract
BACKGROUND The Raymond-Roy Occlusion Classification (RROC) is the standard for evaluating coiled aneurysms (Class I: complete obliteration; Class II: residual neck; Class III: residual aneurysm), but not all Class III aneurysms behave the same over time. METHODS This is a retrospective review of 370 patients with 390 intracranial aneurysms treated with coil embolization. A Modified Raymond-Roy Classification (MRRC), in which Class IIIa designates contrast within the coil interstices and Class IIIb contrast along the aneurysm wall, was applied retrospectively. RESULTS Class IIIa aneurysms were more likely to improve to Class I or II than Class IIIb aneurysms (83.34% vs 14.89%, p<0.001) and were also more likely than Class II to improve to Class I (52.78% vs 16.90%, p<0.001). Class IIIb aneurysms were more likely to remain incompletely occluded than Class IIIa aneurysms (85.11% vs 16.67%, p<0.001). Class IIIb aneurysms were larger with wider necks while Class IIIa aneurysms had higher packing density. Class IIIb aneurysms had a higher retreatment rate (33.87% vs 6.54%, p<0.001) and a trend toward higher subsequent rupture rate (3.23% vs 0.00%, p=0.068). CONCLUSIONS We propose the MRRC to further differentiate Class III aneurysms into those likely to progress to complete occlusion and those likely to remain incompletely occluded or to worsen. The MRRC has the potential to expand the definition of adequate coil embolization, possibly decrease procedural risk, and help endovascular neurosurgeons predict which patients need closer angiographic follow-up. These findings need to be validated in a prospective study with independent blinded angiographic grading.
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Affiliation(s)
- Justin R Mascitelli
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Henry Moyle
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Eric K Oermann
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Maritsa F Polykarpou
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aanand A Patel
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Amish H Doshi
- Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Yakov Gologorsky
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Joshua B Bederson
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aman B Patel
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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